Embodiments of the disclosed technology relate to a liquid crystal panel, a TFT (thin film transistor) array substrate and a manufacturing method thereof.
A liquid crystal panel mainly comprises a TFT array substrate and a color filter substrate bonded with each other with a liquid crystal layer injected therebetween. A sealant (seal agent) is interposed between the peripheries of the TFT array substrate and the color filter substrate to seal them. The TFT array substrate comprises a plurality of gate scanning lines and a plurality of data scanning lines which are crossed with each other so as to define pixel units. Each of the pixel units is provided with a thin film transistor and a pixel electrode. A common electrode and color resin films corresponding to each pixel unit are provided on the color filter substrate.
A voltage is applied to a gate scanning line so that the source electrode and the drain electrode of the corresponding TFT are electrically communicated. Because the data scanning line is connected with the source electrode of the TFT and the drain electrode of the TFT is connected with the pixel electrode, the pixel voltage on the data scanning line can be applied to the pixel electrode and can be hold. A electrical filed is formed between the pixel electrode on the TFT array substrate and the common electrode on the color filter substrate due to voltage on the pixel electrode so as to control the light transmittance and display an image.
A common electrode for forming a storage capacitor with the pixel electrode is also provided on the TFT array substrate. In order to ensure the potential of the common electrode on the TFT array substrate is the same as that of the common electrode on the color filter substrate, the common electrodes on the TFT array substrate and the color filter substrate should be connected together. A simple process for this in the prior art is shown in FIG. 1. Conductive balls 12 are provided inside the sealant 11, and a through hole is formed in the location corresponding to the common electrode 13 on the TFT substrate in the region for applying the sealant 11. A metal layer 14 is deposited in the through hole so that the common electrode 13 on the TFT substrate is electrically connected with the conductive balls 12 via the metal layer 14, and further electrically connected with the common electrode 16 on the color filter substrate 15.
During performing the above solution, the inventor has found that the prior art have at least the following problems. As shown in FIG. 2, because the conductive balls 12 in the sealant 11 are easy to accumulate static electricity, a electrical filed generates between the conductive balls 12 and the data scanning line 17 on the TFT array substrate and can break down a protection layer 18 on the data scanning line 17, so that a electricity leaking phenomenon of the data scanning lines occurs and the normal displaying function is influenced. In addition, the above problem can also exist on the gate scanning lines.